Henrik christian fredrik stormer



(No Model.)

H. G. F. STORMER. APPARATUS FOR WASHING AMALGAM.

Patented Mar. 8, 1898.

Winlddwf NiTn STATES PATENT FFICE.

APPARATUS FOR WASHING AMALGAM.

SIPEOIFIGATION forming part of Letters Patent No. 600,211, dated March 8, 1898. Application filed June 26,1895. Serial No. 554,083. (No model.)

To aZZ whom, it may concern:

Be it known that I, I'IENRIK CHRISTIAN FREDRIK SToRMER, a subject of the King of Sweden and Norway, residing at Ohristiania, in the Kingdom of Norway, have invented certain new and useful Improvements in Apparatus for lVashing Amalgam; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters of reference marked thereon, which form a part of this specification.

In the electrolytic decomposition of aqueous solutions of the salts of the metals of the alkalies in contact with a mercury cathode detrimental secondary reactions take place, resulting from the reaction of the separated metal upon the water of the electrolyte,whereby the latter is decomposed, giving rise to undesirable secondary products and consequent loss of electric energy. This reaction of the separated metal upon the water of the electrolyte takes place whether the mercury cathode is quiescent or flowing continuously to and from the apparatus. In the former case the reaction of the metal upon the water of the electrolyte is due chiefly to the fact that the mercury becomes saturated with the metal to such a degree as to reduce its power of absorption too much, while when the oathode is flowing continuously it carries along with it a certain quantity of water from the electrolyte,which is immediately decomposed.

From what has been said it will be seen that the main difficulty lies in maintaining the surface of the mercury in contact with the electrolyte in a quiescent state and at the same time preventing too great an accumulation of metal in the surface stratum of the mercury.

I have found by actual practice both with a flowing and a quiescent cathode that it is possible to obtain and maintain in contact with the electrolyte quite a distinctive or separate thin layer or film of amalgam,while the body of mercury below such film can be kept in constant agitation without destroying said layer or film. It is therefore evident that the tendency of the surface layer to decompose the water of the electrolyte decreases in proportion to theincrease of the power of absorption of the body of mercury underlying said layer or film and containing a less percentage of metal than said layer or film. If, on the other hand, a permanent thin surface layer or film of mercury containinga high percentage of metal is provided and the body of mercury underlying said layer is agitated or mixed up, the power of absorption of the mercury cathode is more energetic and capable of completely coi nteracting the tendency to decomposition of the water of the electrolyte, and this is the case whether the mercury cathode is quiescent or flowing continuously. Accordingly the electrolytic decomposition of solutions of the salts of the metals of the alkalies may be effected in presence of or in contact with a quiescent or a continuouslyallowing mercury cathode, provided a more or less concentrated practically quiescent thin layer or film of amalgam is maintained in contact with the electrolyte while the body of mercury underlying such layer or film is continuously agitated to prevent the accumulation of metal in said surface layer or film, and consequently the increase in the depth or thickness thereof, by mixing the metal separated and passing through the film with such underlying body of mercury.

In case the mercury cathode is a quiescent one the electrolytic decomposition is of course intermittent, as it becomes necessary to remove the cathode before the amalgam becomes too much concentrated, while the op eration is made a continuous one with a flowing cathode.

The construction of apparatus suitable for the carrying out of my invention, particularly the means for stirring the body of mercury Without disturbing or breaking up the surface film of practically quiescent amalgam, may be variously modified, as shown in the accompanying drawings, in which-- Figure 1 is a vertical longitudinal sectional view of one form or construction of apparatus, and Figs. 2 and 3 are like fragmentary Views illustrating structural modifications.

Referring to Fig. 1, which illustrates an electrolytical apparatus in which provision is made for a continuous flow of the mercury cathode through such apparatus, A indicates a Vessel of suitable form and material, preferably of a non-conducting material, as earth-- enware, cement, or the like, provided with a cover B, a feed branch or port J, an overflow or exhaust branch or pipe K, and a branch or pipe L for drawing off the gases evolved at the anode. A pipe E, connected with the vessel A at one end and near its bottom and terminating in a funnel-shaped mouth, serves to :supply the apparatus with mercury, a discharge-pipe leading from near the bottom of said vessel at its opposite end into a trap F, closed by a suitable stuffing-box H, in which the bent end of the eduction-pipe G is adjustable for the purpose of adjusting or Varying the depth of mercury in vessel A. If the vessel A is constructed of a non-conductive material, I place upon the bottom thereof a conductive plate 0, as a plate of cast-iron, which is connected with the negative pole of the source of electricity, the upper surface of the plate being preferably planed or otherwise trued to a substantiallyplane surface,

over which the mercury is caused to flow.

From the cover B of vessel A depends a tubular guide sleeve S for a rod N, whose lower end is guided in a step or socket R in the bottom of the vessel A, the upper end of said rod being connected to an eccentric O on a shaft P, the guide-sleeve S dipping into the stratum of mercury D. To the lower end of rod N, at a suitable distance from the conducting-plate O, is secured a perforated plate M, which may be of iron, ebonite, or other suitable material or substance not injuriously affected by the mercury cathode, and at a suitable distance above the latter is arranged the anode, which is preferably composed of aframe U, in which a series of carbon rods T are secured in the form of a grating, said frame being supported from brackets V on the inner face of the walls of vessel A. It is obvious that when the shaft P is revolved a Vertical reciprocating motion is imparted to the plate M, and as this plate is perforated the mercury is forced through the perforations of the plate at each upward and downward movement thereof. In the upward movement of the plate the mercury is caused to flow in a downward direction, carrying along with it the greater part of the amalgam formed, while during the downward movement of the said plate the mercury is caused to flow upwardly through the perforations thereof, thereby elfecting an intimate admixture of the separated metal or amalgam formed with the whole of the body of mercury, and if the flow of such mercury through the vessel is properly regulated the outflowing amalgam will contain a much higher percentage of metal than would be the case otherwise. The electrolyte is fed in a continuous regulated stream through feed-port J and flows off through overflow-pipe K, while the mercury in a continuous stream is fed to the apparatus through pipe E and flows out of the apparatus through pipe G, and it is obvious that if the inflow and outflow of the mercury, as well the outflow-level, are suitably regulated there will at all times be a substantially quiescent layer of amalgam in contact with the electrolyte. On the other hand, by suitably regulating the amplitude of reciprocation of the perforated plate M the thickness of the practically quiescent surface layer or film of amalgam can also be determined and the amalgam formed, which would otherwise increase the thickness of the surface layer, is mixed with the body of mercury underlying said surface layer without cury over the riffles or corrugations and imparting to such mercury the desired motion whereby the mixture of the metal or amalgam throughout the body of mercury is effected, the mercury being in this arrangement directly connected with the negative pole of the electrical source.

In Fig. 3 I have shown the vessel A provided with a false bottom M provided with riffles or corrugations or equivalent devices,

said false bottom or plate being connected by rod N to any suitable device, as an eccentric, adapted to impart to said plate a reciprocat ing motion in a horizontal plane, the cathode being a non-flowing-vl. e., a quiescentone, the admixture of the metal or the distribution of the amalgam throughout the body or bulk of mercury being effected by the reciprocating or jigging motion of the plate.

In Fig. 2 I have shown the riftles or corru-.

gations in the form of saw-teeth inclined toward the outflow-port, so as to facilitate the flow of the cathode in that direction, while in Fig. 3 the riflles or corrugations consist of parallel ribs of polygonal form in cross-section. The form of these ribs and the depth of the intermediate depressions may, however, be varied, as indicated at the right-hand end of the plates M and M as the conditions of service may require.

It will therefore be seen that the means for carrying my invention into practical operation may be varied in many ways without departing from-the spirit thereof, the essential feature of which consists in maintaining a practically quiescent thin stratum or film of amalgam in contact with the electrolyte and imparting to the body of mercury underlying said stratum or film such a motion as to mix therewith the metal separated and passing through the film and which would otherwise accumulate on the surface of the cathode and react upon the electrolyte.

Having thus described my invention, What I claim as new therein, and desire to secure by Letters Patent, is-

1. In an electrolytic apparatus, the combination with a suitable vessel containing a layer of mercury as cathode and a suitable anode, of a mixer consisting of a plate normally immersed in and of substantially the same superficial area as that of the cathode, and means for imparting to said plate a reciprocating motion, for the purpose set forth.

2. In an electrolytic apparatus, the combination with a vessel containing a layer of 

